Mucilaginibacter formosus sp. nov., a bacterium isolated from road-side soil

Abstract

A Gram-stain negative, aerobic, non-motile and rod-shaped novel bacterial strain, designated as MAH-5(T), was isolated from a road-side soil sample and was characterised by using a polyphasic taxonomic approach. The colonies were observed to be yellowish orange in colour, smooth, circular and 0.3-0.7mm in diameter when grown on nutrient agar for 2days. Strain MAH-5(T) was found to be able to grow at 15-35 degrees C and at pH 4.0-8.0. The strain was observed to be positive for both the catalase and oxidase tests. Cells were found to be able to hydrolyse aesculin, gelatin and starch. By 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Mucilaginibacter and to be closely related to Mucilaginibacter panaciglaebae BXN5-31(T) (98.35%), Mucilaginibacter soyangensis HME6664(T) (97.82%), Mucilaginibacter antarcticus S14-88(T) (97.49%) and Mucilaginibacter ximonensis XM-003(T) (97.06%). In DNA-DNA hybridization tests, the DNA relatedness values between strain MAH-5(T) and its close phylogenetic neighbors were below 45.0%. The genomic DNA G+C content of strain MAH-5(T) was determined to be 41.5mol% and the predominant isoprenoid quinine was identified as MK-7. The major fatty acids were identified as C-15:0 iso and summed feature 3 (comprising C(16:1)7c and/or C(16:1)6c). The genetic characteristics, in combination with chemotaxonomic and physiological data, demonstrated that the isolated strain MAH-5(T) represents a novel species within the genus Mucilaginibacter, for which the name Mucilaginibacter formosus sp. nov. is proposed, with MAH-5(T) as the type strain (=KACC 19291(T)=CGMCC1.16489(T)).